Question

There are four stages in the healing of a bone fracture. Which of the following best illustrates the sequence of these stages: 1. bony callus formation 3. fibrocartilage callus formation 2. bone remodeling 4. hematoma formation

Answer 1

The sequence of stages in the healing of a bone fracture is hematoma formation, fibrocartilage callus formation, bony callus formation, and bone remodeling.

Step-by-step explanation:

The sequence of stages in the healing of a bone fracture is as follows:

1. Hematoma formation: When a bone breaks, blood vessels tear and hemorrhage, resulting in the formation of clotted blood or a hematoma at the site of the break.
2. Fibrocartilage callus formation: Within days of the fracture, fibroblasts and osteoblasts enter the area and begin to reform bone. Fibroblasts produce collagen fibers that connect the broken bone ends, and osteoblasts start to form spongy bone. The repair tissue between the broken bone ends is called the fibrocartilaginous callus.
3. Bony callus formation: The fibrocartilaginous callus is converted into a bony callus of spongy bone. Cartilage becomes ossified, and osteoblasts, osteoclasts, and bone matrix are present.
4. Bone remodeling: The bony callus is remodeled by osteoclasts and osteoblasts, with excess material being removed. Compact bone is added to create bone tissue similar to the original bone.

Answer 2

Fibrocartilage callus formation is the correct answer.

Step-by-step explanation:

A: Bony and cartilaginous material forming a connecting bridge across a bone fracture during repair. Within one to two weeks after injury, a provisional callus forms, enveloping the fracture site.

B: A fibrocartilage callus is a temporary formation of fibroblasts and chondroblasts which forms at the area of a bone fracture as the bone attempts to heal itself. The cells eventually dissipate and become dormant, lying in the resulting extracellular matrix that is the new bone.

C: Bone remodeling is a lifelong process where mature bone tissue is removed from the skeleton and new bone tissue is formed. These processes also control the reshaping or replacement of bone following injuries like fractures but also micro-damage, which occurs during normal activity.

D: Hematoma is generally defined as a collection of blood outside of blood vessels. Most commonly, hematomas are caused by an injury to the wall of a blood vessel, prompting blood to seep out of the blood vessel into the surrounding tissues.